Modeling of Excess Molar Volumes of [Difurylmethane + (Acetonitrile or Propionitrile or Benzonitrile)] Binary Mixtures Using the Prigogine – Flory – Patterson Theory

The recently reported experimental excess molar volume data for {difuryl methane + (acetonitrile or benzonitrile or propionitrile)} binary mixtures as a function of composition at T = 298.15 K under atmospheric pressure, have been used to test the applicability of Prigogine-Flory-Patterson theory. Analysis of each of the three contributions to the experimental excess molar volume vis. the interactional, the free volume and the characteristic pressure terms, show that the interactional and the free volume contributions were negative for all three {difuryl methane + (acetonitrile or benzonitrile or propionitrile)} binary mixtures. The characteristic pressure contribution was negative for {difuryl methane + (acetonitrile or propionitrile)} and positive for (difuryl methane + benzonitrile). The relatively large magnitude of the interactional contribution which arises from dipole-dipole interactions between difurylmethane and the nitrile molecule determined the overall experimental shape of the excess molar volume isotherms for {difuryl methane + (acetonitrile or benzonitrile or propionitrile)} binary mixtures. The correlation between the theoretical and experimental excess molar volumes data was satisfactory for each of the three binary systems.